Propelling and steering mechanisms for trucks and the like



E. J. WILSO N Nov. 16, 1937.

2,099,944 PROPELLING AND STEERING MECHANISMS FOE TRUCKS AND THE LIKE Original Filed April 12, 1934 4 Sheets-Sheet l O wlwlalw v blvlw iiiialmr lii INVENTOR. MERY d. WILSON. BY W \J HIQATTORNEYS Nov. 16, 1937. E. J. WILSON 2,099,044

PROPELLING AND STEERING MECHANISMS'FOR TRUCKS AND THE LIKE Original Filed April 12, 1934 4 Sheets-Sheet 2 IN VENTOR.

y BY $555;

w A ATTORNEYs.

Nov. 16, 1937. E. J. WILSON 2,099,044

PROPELLING AND STEERING MECHANISMS FOR TRUCKS AND THE LIKE Original Filed April 12, 1934 4 Sheets-Sheet 3 //9' s F I JL FIGS.

5 M5 I m 2 l I i i I 3 o 63 I I 4 L F We 0 FIG.3.

INVENTOR.

TTORN E Y5 I EMERY u. wn. 0 N ,4 BY

Nov. 16, 1937; E. J. WILSON 2,099,044

PROPELLING AND STEERING MECHANISMS FOR TRUCKS AND THE LIKE Original Filed April 12, 1934 4 Sheets-Sheet 4 INVENTOR. EMERY J. ILSUN BY 8 W g w M H]; ATTORNEY:

Patented Nov. 16, 1931 PROPELLING AND STEERING MECHANISMS FOR TRUCKS ANDTHELIKE Emery J. Wilson, Cleveland, Ohio, assignor to Thew Shovel Company, Lorain, Ohio, a cor- D nation of Ohio Original application April 12, 1934, Serial No. 720,278. Divided and this application May 8, 1936, Serial No. 78.678

Claims.

This invention relates to improvements in propelling mechanisms for trucks, and more particularly relates to travel mechanism for trucks of the endless tread or track laying and locomotive crane types supporting load handling and excavating superstructures.

Trucks of the track laying type or endless tread type, familiarly termed crawlers, are usually propelled from the power unit on the superstructure through the provision of suitable gearing and clutches whereby driving rollers engaging each of the endless treads may be uniformly driven to cause the truck to travel in a straight ahead or reverse direction, or may be selectively disengaged to cause turning of the truck.

The present application is a divisional application from applicants co-pending application, Serial No. 720,278, filed April 12, 1934 now Patent #2,062,385 issued Dec. 1, 1936, for Propelling mechanism for trucks. The said copending application, Serial No. 720,278 is directed to the transmission for an endless tractor permitting steering by driving whereas the present applica-.

tion is directed to the clutch actuating means to efiect steering by driving.

I have'provided an improved propelling mechanism for trucks of the above type whereby the truck may be driven in a straight ahead or reverse direction and at two different speeds.

It is an object of my invention, therefore, to provide an improved propelling mechanism for trucks of the above type.

Another object of my invention is to provide an improved propelling mechanism for trucks of the above type whereby the truck may be efficiently propelled at two different speeds from a constant speed power unit.

Another object of my invention is to provide an improved propelling mechanism for load handling and excavating machines mounted upon a truck and provided with a single source of power.

Another object of my invention is to provide an improved travel mechanism whereby power may be delivered to a truck drive shaft to cause it to rotate in either direction and at two difierent speeds from a power unit disposed on a superstructure rotatable upon the truck.

Another object of my invention is to provide an improved propelling and steering mechanism for trucks of the power-steered type whereby the truck may be caused to turn on a relatively short or long radius and at two different speeds for each said radius turns.

Another object of my invention is to provide an improved propelling and steering mechanism for trucks whereby the truck may be caused to turn when traveling in a straight-ahead or reverse direction at two difierent speeds.

. Another object of my invention is to provide an improved control mechanism for trucks of the power-steered type whereby the truck may be caused to turn in either direction from the direction of travel and on a relatively short or long radius turn through manipulation of a single lever.

These and other objects of the invention will become increasingly apparent from a consideration of the following description and drawings wherein:

Fig. 1 is an elevational view of a power shovel embodying my invention, with some of the parts removed for simplicity of illustration;

' Fig. 2 is an enlarged fragmentary view of a portion of the power shaft mechanism taken on line 2--2 of Fig. 1;

Fig. 3 is a transverse vertical sectional view of the truck, taken along the lines 3-3 of Fig. 1', and of the superstructure rotated through 90 as illustrated in Fig. 1;

Fig. 4 is a plan view partially diagrammatic taken along line.4--4 of Fig. 3, illustrating the clutch actuating mechanism;

Fig. 5 is a transverse sectional view taken on line 5-5 of Fig. 4;

Fig. 6 is afragmentary sectional view taken along line 6-6 of Fig. 4;

Fig. 7 is an elevational view of manual control levers which I may employ;

Fig. 8 is a view partially diagrammatic of a quadrant adapted to maintain one of the levers illustrated in Fig. 7 in a plurality of operative positions;

Fig. 9 is a fragmentary elevational view showing the method of mounting the manual control lever of Fig. 2.

Referring to the drawings, I have indicated the truck generally at I 0, the superstructure rotatably supported upon the truck at H, and the travel mechanism at l2. The superstructure comprises generally a frame l3 including a sectional turntable l4, rearwardly inclined posts I5 pin-connected at their bases to the turntable and supcombustion engine, drives a pinion 2| through suitable clutch means, the pinion 2| driving a gear 22 by means of a silent chain 23. The gear 22 together with a pinion 24 integral therewith is rotatably mounted on a center drive shaft 25 preferably by antifriction bearings, the shaft 25 being fixedly mounted between the spaced posts l5, by means not shown but well known in the art. The pinion 24 meshes with a gear 26 keyed to a horizontal swing shaft 21, the swing shaft being rotatably mounted transversely of posts l5 by suitably bushed split bearings provided therein but not shown, being of well known construction. The swing shaft 21 will thus be continuously rotated during operation of .the motor. The horizontal swing shaft 21 has rotatably mounted thereon adjustably spaced pinions 28 and 29, each of the pinions having integral therewith a clutch drum as indicated at 30 and 3| respectively.

A pinion 21a. on the shaft 21 drives an idler gear 2511 on the shaft 25, and the latter may be used to'operate a boom hoist drum, not shown, but these parts constitute no essential part of the present invention.

Also mounted on the shaft 21 and splined therewith are grooved sleeves 32 and 33 each operably connected to'an internally expanding type friction clutch 3434 adapted to frictionally engage the inner face of clutch drums 30 and 3| by axial movement of the sleeves 32 and 33. The movement of the sleeves 32 and 33 is manually controlled in a manner to be later described, whereby the pinions 28 and 29 may be selectively coupled to and caused to rotate with the shaft 21.

4 The pinions 28 and 29 are each meshed with a bevel gear 35 coupled to a vertical swing shaft 36 rotatably supported by the frame I3. The horizontal swing shaft 21 continuously rotates in a clockwise direction as viewed in Fig. 1, and the pinions 28 and 29, being confrontingly mounted on the shaft 21, will cause the bevel gear 35 to be rotated in reverse directions about a vertical axis dependent on which pinion is selectively coupled to the shaft 21.

The bevel gear 35 performs the dual function of operating the vertical swing shaft 36 to swing the superstructure relative to the truck and of operating the travel mechanism in a manner to be described -to propel the truck. The shaft 36 by means of a jaw clutch 31 is rotatably coupled with a pinion 38 meshing with and having planetary action relative to a gear 39 fixed to the truck whereby the superstructure may be swung in either direction dependent upon the direction of rotation of the bevel gear 36 as effected by the pinion 28 or 29.

The bevel gear 35 also meshes with'a bevel pinion 40 keyed ,to one end of an inclined travel shaft 4| rotatably mounted on the turntable by means of spaced bearings as indicated at 42 and 43. The direction of rotation of the travel shaft 4| will be determined by selectively coupling the pinion 28 or 29 with the horizontal swing shaft. Loosely mounted onthe travel shaft 4| are spaced bevel pinions 44 and 45 each of said pinions being provided with clutch segments in confronting faces thereof, whereby they may be selectively coupled to the travel shaft by means of an intermediately disposed jaw clutch member 45 splined to the travel shaft. The jaw clutch member 46,adapted to be engaged or disengaged fromv the aforementioned pinions by movement a a y on the travel shaft, is manually controlled through lever means to be described.

The travel shaft pinions 44 and 45 are each meshed with a vertically mounted bevel gear 41, the gear 41 being mounted on a center pin 48 about which the turntable and superstructure rotate. The gear 41 can be caused to rotate in either direction dependent upon the direction of rotation of the travel shaft 4| and at either of two different speeds dependent upon whether pinion 44 or pinion 45 is driving the gear. It will be apparent by reference to Fig. 3 that when the travel shaft 4| is rotating in a given direction, engagement of the gear 41 with the pinion 44 will cause the gear 41 to rotate in one direction, and engagement of the gear 41 with the pinion 45 will cause the gear 41 to rotate in a reverse direction, so that when it is desired to continue traveling in a'given direction and at a different speed and when one of the pinions 44 or 45 is rendered inoperable to drive the gear 41 and the other is rendered operable, that the shaft 4| will be reversed in direction by the friction clutches 34 on the horizontal swing shaft.

Thus, with the aforementioned clutch and gear train initiated at the motor, power is transmitted to the gear 41, the friction clutches 34 on the horizontal swing shaft 21 being selectively operable to determine the direction of rotation, and the jaw clutch on the travel shaft being selectively movable to determine the speed of rotation.

The aforementioned gear and clutch train affords a relatively direct, eflicient, and compact means of transmitting power to the travel mechanism. This is effected independently of the boom control, hoist, dipper stick, or similar control operations and these operations, if desired, may be carried on concurrently with truck travel. Since the same bevel gear 35 controls the travel mechanism and the swing mechanism, the swing mechanism is normally disengaged during travel, there being no occasion for concurrently effecting travel and swing movements.

The center pin 48 upon which the bevel gear 4'! is mounted is rotatably supported generally centrally of the truck body, in a hub 50 integral therewith, the lower end of the center pin having integrally formed therewith a bevel pinion 5| meshing with a gear 6| adapted to be coupled to the crawler drive shafts.

The truck body generally indicated at 55, and preferably formed of cast metal, is of rugged inverted box form construction and is rigidly connected by channel or the like frame members to fixed end axles 51, and intermediately disposed driving axles 56, the axles 51 forming a mounting for idling rollers 58. Driving rollers 59 are rotatably mounted relative to the frame 55 and are adapted to be driven by the axles 56 in a manner to be later described. The rollers 58 and 59 are engageable with and rotate upon an endless tread 6ll whereby the truck will be propelled in a manner well understood.

The bevel pinion 5| of the center drive pin 46 meshes with a bevel gear 6| integrally mounted upon a hollow shaft 62 rotatably mounted upon relatively reduced end bearing portions of the driving axles 56 projected into the shaft ends, the driving axles 56'being',suitably mounted as previously described by frame members secured to the truck body. The shaft 62 at each end is provided with relatively enlarged outwardly disposed clut h faces 63 engageable with axially movable jaw clutch members 6464 splined to the driving axles, whereby the driving axles may be independently or concurrently rotated by the gear 8|; The jaw clutch members 84 are also adapted to be locked with clutch faces 85 secured to the truck frame members, whereby either driving axle may be selectively locked against rotative movement.

Normally, both driving axles will be coupled with the shaft 82 to propel the truck in a straight ahead position. When it is desired to turn the truck one of the driving axles will be disengaged, whereby one tread will be propelled and the other may be idly moved to effect a relatively long radius turn. To effect a short turn, the disengaged axle, rather than being permitted to idle, is

locked to the truck frame by means of the clutch face 85 preventing movement of its associated tread.

There are two central treaddriving rollers 59 on each side of the truck, each being provided with an integral gear portion I I 8 meshed with an intermediate pinion 88. The rollers 59, as previously stated, are engageable with the endless tread 88 through interengaging tooth and sprocket portions. The pinions 86 are fixed to the outer ends of the axles 58 and are rotatable therewith, the axles 58, by means of the jaw clutch members 84-64 splined thereon, being adapted to be'selectively engaged either with the clutch face 83 or the clutch face 85 which is fixed to the truck frame. Since the clutch face 85 is fixed to the truck frame, interengagement of the member 84 therewith will prevent the axle 58 and its associated pinion 88 from rotating, and consequently the gear portion 8 integral with the roller 59 will be prevented from rotating, thereby maintaining the endless tread 89 in a fixed position relative to the truck frame.

Thus, when one of the endless' treads 88 is maintained fixed by the coupling member 84 and the clutch face 85, and the opposite tread is driven through coupling clutch member 84 and the clutch face 83 of the shaft 82, the truck will be turned relatively more sharply than if the jaw clutch member 84 were in an intermediate position permitting the locked tread to rotate idly without being driven.

The various clutches so far described and whether-of the friction or jaw clutch type are operable in a generally similar manner by movement of a grooved sleeve axially of the shaft on which its associated clutch is mounted, the sleeve movement being effected by manually operable levers and suitable link connections. These various lever mechanisms will now .be described.

The various operating levers are mounted so ,as to be easily accessible to the operator, the v levers controlling the swinging of the superstructure, derricking of the boom, and the drum hoist being preferably mounted on a common shaft 18 secured to a plate 18a supported laterally of the turntable as is also the lever controlling the engine clutch. The levers controlling the steering, travel, and a lever controlling the swinging of the superstructure being mounted on a. common shaft II, the shaft ll being spaced upwardly from the turntable by a bracket 12 and. a collar engaging the strut IS. -'The levers controlling derrickingof the boom, the hoist drum, and kindred operations, constitute no essential part of my present invention and can be of any suitable type well under stood in the art.

The swing lever 18 which actuates the sleeves 32 and-33 axially of the horizontal swing shaft to selectively couple the pinions 28 and 29 therewith through friction clutches 34, is rotatably mounted on the shaft I and is provided with a depending arm 11. As best illustrated in' Fig. 9, the arm I1 is linked by a connection 18 to one arm of a pivoted crank I8 supported by the plate 18a, the opposite arm of the crank being adapted to transmit movement horizontally and generally at right angles to the connection 18 to a. rod 88. Thus, rotative movement of the swing lever 18 about its shaft will transmit horizontal movement transversely of the turntable to the rod 88 through the aforementioned link means.

Fixedly secured to therod 88 at spaced points by means of an intermediately disposed spacing' sleeve are fixed collars 8| and 82. Adjacent each 1 of the fixed collars 8| and 82 are resiliently and axially movable cooperating centering springs 83 and 84. The collar BI and spring 83 have disposed therebetween the forkedlower end of a yoke member 85'which partially encircles the rod 88. Substantially midway of the yoke member 85 it is provided with a pivotal support 85a secured to the turntable, the upper or yoke end being provided with pins directed-inwardly towards and radially of the horizontal swing shaft 21. The yoke pins engage the sleeve 32 and effect axial movement of the sleeve to engage or disengage the pinion 28 from the shaft 2'1. Thus, upon movement of the fixed collar 8! outwardly relative to the turntable through the link means described,

the pinion 28 will be coupled to the shaft. In like manner, a yoke member 81 controls the engagement and disengagement of the pinion 29 with the shaft 21 through actuation of the fixed collar 82. Movement of the lever 18 upon either side of a neutral position will selectively couple the pinions 28 and 29 with the shaft 21 and upon release of the lever it will be returned to the neutral or disengaged position relative to both pinions, by means of the resiliently movable centering springs 83 and 84. Thus, to effect swinging of the superstructure or to propel the truck, the gear 35 will be caused to rotate in a desired direction by the above described lever means. The swinging of the superstructure will be efiected first by selectively coupling gear 35 with pinion 28 or 29 to selectively rotate gear 35 in reverse directions. This is accomplished by manipulation of lever I8 as just described. Secondly, jaw clutch element 31 mustbe operably connected with shaft-38 and its associated pinion 38. As previously described, pinion 38 upon being rotated will have planetary action relative to the truck due to its engagement tion of jaw' clutch element 31. is controlled by a lever l4! in a manner hereinafter described. Thus, both lever 18 mounted on shaft 18 and lever I mounted on shaft ll must be manipulated to effect swinging of the superstructure in a desired .direction.

The lever means actuating thejaw clutch member '48 mounted on thetravel shaft to selectively couple the bevel pinions 44 or 45 with the shaft will now be described. The hand operable control lever effecting this result is termed the'travel lever, indicated at 88,rotatably mounted on the shaft II and provided with a laterally extending sleeve'telescoped over theshaftr The sleeve has integral therewith a forked arm 88 extending radially from the shaft II and engageable by pinion 44, thereby coupling the pinion to the travel shaft, whereby the truck may be propelled at a given speed; movement of the lever 86 in a reverse direction will couple the pinion 45 with the travel shaft to propel the truck at a different speed, and in an intermediate or neutral position of the lever 86 neither pinion will be coupled to the travel shaft. To maintain the lever in a desired position, it is provided with a spring operable detent adapted to lock with a quadrant 99.

The swing lever 16 will, in a manner previously described, effect the direction of rotation of the travel shaft and the travel lever 86 will effect the speed at which the truck is propelled, as hereinbefore more fully described.

The manner of effecting steering of the truck will now be described. A steering lever 93 rotatablyfixed to the shaft II, upon which the travel lever 86 is also mounted, is adapted by means of a detent engageable with a quadrant -94 to be locked in a desired position in a manner similar to the lever 86. Movement of the lever 93 will rock the shaft 'II and a laterally extending crank 95 rigidly secured thereto, the crank 95 being pivotally connected intermediate the arms of a yoke member 96, whereby a vertical movement will be transmitted to the yoke 96 by rotative movement of the steering lever 93. The yoke 96 is adjustably secured to a rod 91 projected through and movable axially of the vertically disposed center pin 48, the lower end of the rod 91 being connected to a trunnion block 98 disposed laterally of and adapted to rock a shaft 99 rotatably mounted generally centrally and longitudinally of the truck. A depending arm I90, rigidly secured to the shaft 99 and bifurcated at its lower end, is pin connected to a clutch actuating mechanism MI by which rock shafts I01 and I08 supported in bearings on the main frame or superstructure are oscillated to reciprocably operate the clutches 6464 by means of depending pairs of arms II l-I II and II2--I I2 engaged at their lower ends by pins in the above-referred to grooves in the clutches.

The rock shafts I91 and I08 have depending therefrom, respectively, arms I09 and H9 by which rocking movement is communicated tothe rock shaft from the said depending arm I09 upon oscillation of the shaft 99 above referred to, by the following means.

A rod I92 pivotally connected to the lower end of the arm I90 has a sleeve spacer I03 thereon abutting upon a circular head I04 of a spring support comprising arms I05 telescoped within a compression spring I06, the rod I02 passing through the head I94 and axially through the spring I96 and through a similar circular head.

I" having arms I05 thereon within the spring, the rod outwardly of the head I" having nuts II9'thereon and having a spacing sleeve 9 between the nuts and the head I". The heads I04 and I" together with the arms- I05 maintain the spring I96 in axial alignment with the rod I92 and it is put under initial compression by the nuts H9. The lower end of the arm I99 is forked and straddles the sleeve H9 and a pin bridging the fork and under the sleeve II9 slidably supports the outer end of the rod I92 and the parts thereon including the spring I06. 1

The arms I95 within the spring I06 may be connected by tie members I 2I-I2I and the rod I92 may have bearings therein to further assist in supporting the spring. At the other side of the arm III is a circular head I22 pivotally connected to the lower end of the arm I and opposite thereto is a head I23, the head having arms I thereon connected by tie members I24-I24 within a spring I25, the spring abutting the two heads. A rod I26 has bearing in the tie members I24 and has a nut I2'l' abut ting one bridge member on one end of the rod, the other end of the rod projecting through the head I23 and having nuts thereon, a sleeve I29 abutting upon the nut ends and upon the head I23. The depending arm H9 at its lower end is forked straddling the sleeve I29 and a pin connecting the forks and under the sleeve I 29 supports the rod I26 and the spring and other parts thereon.

The lower end of the arm I99 has a rounded portion engaging the head II! and the correspending lower end of the arm IIO has a like rounded portion engaging the head I23, and the arms I09 and H9 are held in engagement with the said head by a tension spring H3 hooked at opposite ends into the ends of depending arms II4-I I4 secured to the rock shafts I91 and I98 to which the arms I99 and H9 are secured. All movement'under the force of the tension spring I I3 is limited by the clutches seating in clutch faces 63. Rods II5 are projected through perforations at I3I-I3I in the main frame, and outwardly thereof carrying sleeves I32 and I33. The rods I I5 are used only to hold the clutches permanently disengaged when towing the machine.

By means of the mechanism above described, the arms III-III and II2-II2 are held by the spring H3 in the position to normally engage the clutches 64-64 with the clutch faces 63-63 of the shaft 62, whereby the shaft 62 is normally connected to the driving shafts 56--56 and the driving rollers 59 are normally both coupled with the shafts 56-56 through the pinions 66 on the shafts meshed with the gears II6'-I l6. This normal position of parts corresponds to the middle position of the lever 93 in Fig. 8.

If now the vertical rod 91 is moved downwardly w means of the steering lever 93, it will move the arm I00 to the right as viewed in Fig. 6 and compress the spring I25 and through the arm 9 will rock the shaft I98, moving the corresponding clutch element 64 to the right as viewed in Fig. 3 causing it to uncouple' its associated shaft 56 from the power shaft 62; and-if the lever 93 is stopped in the next to the middle notch, Fig. 8, the clutch 64 will be in an intermediate or neutral position and not connected to either the shaft 62 or the stationary frame. One tread therefore will not be driven, its driving rollers rotating'idly, and the other tread will be driven by its rollers and the truck will therefore be caused to turn on a relatively large radius. If the lever 93 is, however, moved farther or to the outer notch position, the vertical rod 91 will be moved downwardly farther and will rock the shaft I98 sufllciently to engage the clutch with its associated clutch face 65 secured to the frame. The corresponding driving rollers will be locked against rotative movement which will hold their engaged tread stationary and cause the truck to turn on a relatively short radius. Upon release of the steering lever 93 and its return to normal or central position, the clutch element 64 will again be moved by the spring II3 to couple the corresponding shaft 56 with the drive shaft 62 and the truck will be propelled again straight ahead. Upward movement of the rod 91 by the lever 93 will in a similar manner cause the truck to be turned in the reverse direction on either a long or a short radius in a manner similar to that describedabove. Thus,

upward movement of rod 91 causes arm I to be rocked in a clockwise direction and force spacer sleeve I03 to the left as viewed in Fig. 6 and thereby compress spring I06 to rock arm I09 and shaft I01 in a clockwise direction. This will effect disengagement of the left hand clutch element 64 from the shaft 63, and with continued movement the clutch element will be locked with the truck frame.

In Fig, 8 is illustrated the hand lever 93 adapted to be locked in five different positions whereby, as will now be clear, at thev central position the truck will travel in a straight-ahead direction and at the positions at either side of center it will be caused to turn to the left or right on a long radius and at the extreme outer positions the truck will be caused to turn on a short, radius.

As'stated above, both clutches 64 are always constrained to move toward the straight-ahead position, Fig. 3, by the spring H3, and either clutch when moved to the disengaged or extreme engaged position is under the tension of the spring II3 tending to return it, and each clutch device is moved away from its normal position against the tension of the spring II 3 by the compressive force of the respective springs I08 and I25.

It will be observed that the clutches 34-34 transmitting the propelling power from the horizontal swing shaft 25, are friction clutches; and that the clutches engaging the gears 44 and 45 on the travel shaft M as well as the clutches 64-64 are jaw type positive clutches, but that the clutches B l-64 are resiliently engaged with their corresponding jaw teeth by the spring H3 or the springs I06 and I25. By this means, the operator may move the steering lever 93 directly to the corresponding direction notch and then immediately may use both hands for other purposes. The direction'clutches 64-64 may not immediately engage their corresponding teeth because they do not register therewith or because they are held in their previously engaged position by the friction of'the drive connection therewith, but immediately upon registration or upon a slight change of driving torque which may of itself occur or which may be effected by a with pinion 38 to effect rotation of the turntable will now be described. Referring to- Fig. '7, it

. will be noted that a lever I40 is pivotally mounted on shaft 1| intermediate levers 86 and 93. Movement of lever I40 rocks a crank arm I4I integral therewith to which is secured a generally vertically extending rod I42. The crank portion MI is generally horizontally extending and the rod I42 is pivotally connected therewith whereby rocking movement of the crank portion. I4I will impart a generally vertical movement to rod I42. The rod I42 has a yoke member I43 adjustably fixed tothe lower end thereof and pivotally mounted on the yoke'arm are shoes I44 adapted to engage an annular groove provided in jaw clutch'element 31.

It will now be understood that movement of lever I40 through the transmission; means described will cause axial movement of jaw clutch I element 3l'along the vertical swing shaft 36 to engagement of the jaw clutch element 31 with pinion 38 the swing lever I6 will be operated in a manner previously described to cause rotation of the vertical swing shaft 36 in a desired direction dependent upon the direction in which it is desired to rotate the turntable.

The above described steering and travel conferred embodiment of my invention, I contem plate that numerous and extensive departures therefrom may be made without departing from the spirit of my invention and within the scope of the appended claims.

-- I claim:

1. In a vehicle of the class described, a power delivery shaft, a pair of propelling shafts axially aligned with the power shaft, a pair of clutches each including a slideable clutch element adapted in a first position to rotatably interlock its associated propelling shaft and power delivery shaft "and in a second position to disengage said shafts, a pair of rock shafts each adapted to effect movement of a slideable clutch element, a manually operable lever having a central position and lateral positions on either side thereof, a pair of link means each connecting a rock shaft and the lever, each link means including a spring compressible by lever movement from a central 'to a lateral position to efiect disengagement of its associated propelling shaft from the power delivery shaft, tension means interconnecting each rock shaft and lever opposing spring compressing force on the rock shaft to effect engagement of the disengaged propelling shaft with the power delivery shaft upon return of the lever to the central position.

2. In a vehicle of the class described including a truck frame, a power delivery shaft supported by the frame, a pair of propelling shafts supported by the frame and axially aligned with the delivery shaft, a pair of clutches each including a slideable clutch element adapted in one position to rotatably interlock its associated propelling shaft and the power delivery shaft and in another position to lock said propelling shaft.

with the truck frame, a pair of rock shafts each adapted to effect movement of a slideable clutch element, a manually operable lever, linkmeans interconnecting the lever with each of the rock shafts including a set of springs compressible by lever movement in a given direction to effect disengagement of a clutch connecting the propelling shaft with the power delivery shaft and upon continuous lever movement in the same direction to eifect locking of said propelling shaft with a portion of the truck frame, tension means interconnecting each rock shaft with the lever opposing said compressing movement and adapted upon lever movement in a reverse direction to effect disengagement of the locked propelling shaft from the truck frame and upon continued movement in said reverse direction to eflect engagement of said propelling shaft with the power delivery shaft. I

3. A vehicle of the class described comprising a power delivery shaft, a pair of propelling shafts axially aligned therewith, a pair of slideable clutch elements each adapted to engage and disengage the propelling. shaft with the power delivery shaft, clutch actuating means comprising a pair of rock shafts each connected with a slideable clutch element'and each rockable in reverse directions to move its associated clutch element to engaged and disengaged position, a manually operable lever movable to a plurality of positions including a central position, spring means interposed between the lever and each rock shaft compressible by lever movement from the central position in a given direction to rock its associated rock shaft and clutch element from an engaged to a disengaged position independently of movement of the other rock shaft, tension means interconnecting the rock shafts and the lever opposing movement of a rock shaft to a clutch disengaged position and effecting reverse movement of a rock shaft upon returning the lever to a central position from a clutch disengaged position.

4- A vehicle of the class described comprising altruck frame, a power delivery shaft, 9. propelling shaft,- 9. slideable clutch element adapted in a first position to rotatably interlock the propelling shaft and power delivery shaft, in a second position to disengage said shafts, and in a third position to lock the propelling shaft to the truck frame, clutch actuating means comprising a rock shaft, a manually operable lever movable to a plurality of positions, spring means interposed between the rock shaft and the lever compressible by lever movement from the first and second positions to move the rock shaft an clutch element to disengage the power shaft and propelling shaft, the spring means being further compressible by lever movement to the third position to further move the rock shaft and clutch element in the same direction to lock the propelling shaft to the truck frame, tension means connecting the rock shaft and lever tending to move the rock shaft in reverse direction and effecting disengagement of the propelling shaft and truck frame upon reverse lever movement from a third to a second position, and effecting re-engagement of the power delivery shaft and propelling shaft upon continued reverse lever movement from the second to first position.

5. A vehicle as described in claim 4 and wherein a pair of propelling shafts are provided each operable through its associated rock shaft, spring means, and tension means through lever movement in a similar manner, and lever movement disengaging one of the propelling shafts from the power delivery shaft and locking said shaft to the truck frame increasing the tension on the rock shaft associated with the other propelling shaft and decreasing the force of the spring means thereon to maintain said other propelling shaft engaged with the power delivery shaft.

EMERY J. WILSON. 

